the birds of phi phi le island, krabi, thailand · 2013-07-24 · nat. hist. bull. siam soc....

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NA T. HIST. BULL. SIAM SOC. 27:83-92. 1978. THE BIRDS OF PHI PHI LE ISLAND, KRABI, THAILAND Jeffery Boswalfl and Supradit Kamvanich 2 SU M MARY At least 12 bird species are known or believed to breed on Phi Phi Le island (1.8 sq km) 25 km off the coast of Krabi province, Thailand. Palearctic migrants and off-season seabirds were also observed during the stay (20 November to 7 December). Some details are given of swiftlet nest exploitation by man. INTRODUCTION Phi Phi Le island (7 .4l'N, 98.46'E) in 3.2 km long and 1.2 km wide at its widest point. Its area is about 1.8 sq km. Two islets known to locals as "the children" (Luuk Phi Phi Le) lie about 2 km south-east of the island's southernmost tip. The highest point of the island is 374 m above the sea. With its neighbour Phi Phi Don, it lies abou t 25 km from the western peninsular coast of Thailand. Phi Phi Le is limestone and bounded by dramatic steep, sheer or overhanging cliffs, some over 200 m high.· is one large cave on the east coast. There are two main bays each with short sandy beaches, one on the west coast, and one on the east coast near the south end of the 'island. We camped on the latter. While much rock is exposed there is also a varied and widespread vegetation including tall trees in several places. From the largest forest area of 0.15 sq. km. approximately, some trees have been removed. There are no mangroves. The island has no permanent water or streams. We stayed with two companions on this normally uninhabited island from 20 November until 7 December 1977. Notes were made of all birds seen, though little time was devoted specifically to ornithology. I. Natural History Unit, BBC, Whiteladies Road, Bristol. England. 2. Association for the Conservation of Wildlife, 4 Old Custom House Lane, Bangrak,Bangkok,Thailand.

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Page 1: THE BIRDS OF PHI PHI LE ISLAND, KRABI, THAILAND · 2013-07-24 · NAT. HIST. BULL. SIAM SOC. 27:83-92. 1978. THE BIRDS OF PHI PHI LE ISLAND, KRABI, THAILAND Jeffery Boswalfl and Supradit

NAT. HIST. BULL. SIAM SOC. 27:83-92. 1978.

THE BIRDS OF PHI PHI LE ISLAND, KRABI, THAILAND

Jeffery Boswalfl and Supradit Kamvanich2

SU M MARY

At least 12 bird species are known or believed to breed on Phi Phi Le island (1.8 sq km) 25 km off the coast of Krabi province, Thailand. Palearctic migrants and off-season seabirds

were also observed during the stay (20 November to 7 December). Some details are given of swiftlet nest exploitation by man.

INTRODUCTION

Phi Phi Le island (7.4l'N, 98.46'E) in 3.2 km long and 1.2 km

wide at its widest point. Its area is about 1.8 sq km. Two islets

known to locals as "the children" (Luuk Phi Phi Le) lie about 2 km south-east of the island's southernmost tip. The highest point of the

island is 374 m above the sea. With its neighbour Phi Phi Don, it lies

about 25 km from the western peninsular coast of Thailand.

Phi Phi Le is limestone and bounded by dramatic steep, sheer or

overhanging cliffs, some over 200 m high.· The~e is one large cave on

the east coast. There are two main bays each with short sandy beaches, one on the west coast, and one on the east coast near the south end of the

'island. We camped on the latter. While much rock is exposed there

is also a varied and widespread vegetation including tall trees in several

places. From the largest forest area of 0.15 sq. km. approximately, some trees have been removed. There are no mangroves. The island

has no permanent water or streams.

We stayed with two companions on this normally uninhabited

island from 20 November until 7 December 1977. Notes were made of

all birds seen, though little time was devoted specifically to ornithology.

I. Natural History Unit, BBC, Whiteladies Road, Bristol. England. 2. Association for the Conservation of Wildlife, 4 Old Custom House Lane,

Bangrak,Bangkok,Thailand.

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TilE BIRDS OF PHI PHI LE !SLAr-10 85

The balance, the majority of the frigate birds observed,

fell into one of two categories. On 2 December, 39 out of 121 were all black from below except for an almost circular sharply

contrasting white patch on the belly; this patch extended neither forward of the line of the leading edge, nor rearward of the line

of the trailing edge of the wing. Most of the remaining 82 birds

displayed a much larger area of white extend!ng from the breast

to the line of the trailing edge of the wing; while in a minority the

white extended forward to include the ·head. To judge from the drawings in SLATER (1970), the 39 birds were certainly male

Christmas Island Frigate Birds, Fregata andrewsi. Of the

remainder, the black-beaded birds were almost certainly female andrewsi and the white-headed ones probably immature andrewsi.

The drawings of the male of this species in KJNG et a! ( 1975) and

in LEK AGUL & CnoNIN {1974) appear to be inaccura te.

The record of the Lesser Frigate Bird appears to be the second for Thailand (HoLMEs & WELLs, 1975; LEKAG UL & CnoNIN, ·

1974) and the first for Krabi. The record of the Great Frigate

Bird is the first record specifically from Krabi. The Christmas

Island Frigate Bird has not previously been specifically recorded

from Krabi, but has been collected from neighbouring Phuket

(MEDWAY & WELLS, 1976).

It is worth mentioning that during nearly four years'

residence up to November 1977 in a house on Phuket within sight

of Phi Phi Le, C. B. Frith (personal communication) identified all

three species of frigate bird mentioned above.

Reef Egret, Egretta s,acra. This species was seen daily. All individuals were dark phase. The maximum number seen at one time was 5 around the bay on which we camped, at low tide on 23 November.

The · island population, including one bird on each of the south­easterly off-lying islets, was probably about 15 birds. They fed

not only in the few bays but also along the barnacle-encrusted zone under the cliff over hangs . .C. B. Frith (personal communication) put a Reef Egret off a nest on Phi Phi Le (no date available).

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86 BOSWALL & KANWANJCH

Brahminy Kite, Ha/iastur indus. One or two birds were seen on each

of nine dates between 20 November and 7 December.

Japanese Sparrowhawk, Accipiter gularis. A bird was well seen on 21

November. During three previous weeks this species was identified

frequently in Phuket province after one bird bad been handled,

released and watched in flight (BoswALL & FRITH in press). Thus

we were familiar with the species and we are confident of the

island identification. This is the first record for Krabi.

White-bellied Sea Eagle, Haliaeetus leucogaster. On 31 October 1977

Dawn W. Frith and Donaldo Maciver saw two birds of this

species at Phi Pei Le, the first record of this species for Krabi.

Single birds were seen and heard by us on most days; at least two individuals were involved, one adult and one sub-adult. A nest,

no doubt of this species, was seen in a tree near the top of one of the two off-lying islets.

Osprey, Pandion haliaetus. Single Ospreys were sighted on 23 November

and 5 December. MEDWAY & WELLS (1976) and HoLMEs & WELLs (1975) imply that the Osprey is unrecorded in Krabi, but DICKINSON

(1966) reported a sight record for Phi Phi Don.

Peregrine, Fa leo peregrinus. A male and female were together put off

a cliff on 21 November, a female was seen in the same vicinity on

22 November and 5 December, and a male on 23 November.

Could these birds have been a mated pair? HoLMEs & WELLS ( 1975)

reported two Peregrines in Satun province whose behaviour

suggested the birds may have been paired, all previous Malay

Peninsula records of Peregrines having been of solitary birds. Is

it possible this species breeds in southern Thailand ?

Common Sandpiper, A ctitis hypoleucos. Singletons foraging among barnacle-encrusted rocks were watched on 24 and 28 November

" and on 5 December.

Unidentified terns, Sterna sp. As we approached the island on 20 November and left it on 7 December several terns were seen about the size of Common Terns, Sterna hirundo and quite possibly of that species.

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88 BOSWALL & KANWANICI-I

(in say early March) but the collectors apparently take up resi­

dence on the island two months before that (say early January).

They stay for . a total of about four or five months. This time­

table means that eggs are laid in March and nestlings can be found

at late as early August. A. maximus the larger, so-called "black" species, builds darker nests lowe.r in the cave. These are less

valuable than the "purer", lighter-coloured nests of the smaller ,. so-called "white" swiftlets that attach their nests to the cave walls

at higher elevations.

The national Thai government sells three-year concessions for the exploitation of swiftlet nests. A Phuket company,

Laem Thong, is reliably reported to have paid 2 miilion Baht

(about £50,000) for a concession that covers Phi Phi Le and 10

other islands in the provinces of Krabi, Phangnga and Trang.

Copies of the unpublished paper by Sandbam ( 1978) have

been deposited in the library of the SiamSociety and the Alexander

Library, Oxford~ England. Earlier Thai contributions on the same

subject are those of Dunlap (1907) and Giles (1936).

Black-capped Kingfisher, Halcyon pi/eata. Single birds were seen perched

on rocks at low tide on 25 and 28 November and 3 and 4 December. These are the first records for Krabi province.

Pacific Swallow, Hirundo tahitica. During circumnativation of tye island one bird or a pair were usually flushed from four particular points

low on the cliff, suggesting the occupation of territories. A further

pair was seen on three dates over a particular hill top. This is the first record of this species for Kra bi.

Large-billed Crow, Corvus macrorhynchus. One bird or 2 together were seen on five dates.

White-romped Shama, Copsychus malabaricus. Song heard on 6 and 7 December.

Unidentified thrush (Muscicapidae). A bird perched on limestone seen

clearly but briefly on 3 December was to a European ornithologist

at once reminiscent of a Song Thrush, Turd us philomelus as regards

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90 BOSWALL & KANWANICH

The known or likely breeding birds are: Reef Egret, Bra hminy

Kite, White-bellied Sea Eagle, Black-nest Swiftlet, Edible-nest Swiftlet,

Pacific Swallow, Large-billed Crow, White-rumped Shama, Blue Rock

Thrush, Blue Whistling Thrush, Black-breasted Sundird and probable

Yellow-Backed Sunbird.

Off-season birds from the north either passing throngh the island

or spending the (northern) winter there are Japanese Sparrowhawk,

Osprey, Common Sandpiper, Black-capped Kingfisher, and Ferruginous

Flycatcher.

The 4 visiting seabirds are the Great, Lesser and Christmas Island

Frigate Birds and the unidentified tern.

The one accidental visitor from the local mainland is the Tree

Sparrow.

It must be emphasised that more intensive field work among the

more vegetated areas of the island might well have revealed a few more

nesting species. But even if this bad been shown the island clearly has

no more than an impoverished avifauna.

No other small islands off tbe coasts of the Malay peninsula appear

to have been studied in detail though MEDWAY&WELLS (1976) do

compare the avifaunas of several of the large islands. However,

BRoCKELMAN & NADEE ( 1977) have preliminarily surveyed the avifauna

of the Surin Islands 53 km off the west coast of peninsular Thailand,

north of the isthmus of Kra.

Their biogeographic analysis of the birds of the islands, an up-to­

.date assessment that takes full account of contemporary scientific

thought on the composition of island avian communities generally,

helps us to understand why so few species breed on Phi Phi Le.

Limiting factors probably include the small size of the island, its thin

shape, the absence of fresh water, the fewness of the different habitat

types and the distance of the island from the mainland.

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THE BIRDS OF PHI PHI LE ISLAND 91

ACKNOWLEDGEMENTS

We are grateful to C. B. Frith for introducing us to Phi Phi Le and

to the birds of southern Thailand. Martin Saunders and Donaldo

Maclver assisted with the observations. Jean Stevenson kindly typed

the paper twice and corrected tbe English. The purpose of our stay on

the island was to make a wildlife film for our employers, the BBC.

Warren Brockelman, C.B. Frith, D.A. Holmes, Lord Medway and D.R.

Wells commented helpfully on an earlier draft ot this paper. Michael

J. Sandham collected on swiftlets and two swiftlers themselves that

were kind ly prepared as specimens by Nivesh Nadee. Sandbam was

greatly helped by Arnold and Jooothan Clarke of Phuket.

REFERENCES

BOS\VALL, Jeffery and FRJTH, Clifford B. In p1·ess. First record of the Japanese

Spa rrow hawk, Accipiter gularis on Phuket Island. Nat . 1-ii'st. Bull . Siam Soc. 27

BROCKELMAN, Warren Y. and N /IDEE, Nivesh. 1977. Preliminary survey biogeo­

graphic analysis of tbe birds of the Surin Islands, Thai land. Nat . Hist. Bull.

Siam Soc. 26: 211-226.

DI CK INSON , E. C. 1966 . Notes upon a collection of birds made by Frank Gill Esq.,

off the west coast of peninsu lar Thailand. Na t. E-Jist. Bull. Siam Soc. 21: 243-

249.

DUNLAP , E.P. 1907. The edible bird nest islands of Siam. J. Siam Soc. 4 (3):

1-1 l.

GILES, F. H. 1936. A description of the swifts (Collocaliaf7·ancica and Collocalia

innominata ). the birds which build edible nests. J. Siam Soc. Nat. E-Jist. Suppl.

10:137-160.

H ou·tES D. A. and WELLS, D.R. 197 5. Further observations on the birds of south

Thailand. Nat . l-[JSt, Bull. Siam Soc. 26: 6 l-7 8. ·

KING, Ben, DtCKINSON, E .C. and WOODCOCK, Martin 19 7 5. A Field Guide to the

birds of south-east Asia. Collins. London.

LEKAGUL, Boonsong and C RON JN, Edward 1974. Bird Guide of Thailand. 2nd revised

Edition . Association for the Conservation of Wildlife, Bangkok.

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92 BOSWALL & KAN"IU NICH

MEDWAY, Lord and PYE, J.D. 1977. Echolocation and. systematics of swiftlets. Ch.

19 in B. Stonehouse and · C. Perrins (eds .), Evolutionary Ecology, MacMillan.

MEDWAY, Lord and WELLS, David R. 1976. The Birds of the Malay Peninsula, Vol.

5 Witherby, London.

SAND HAM, Michael J. 197 8. The edible .nest s wiftlets of Kho Phi Phi Leh.

Unpublished typescript. Copies have been deposited in the library of the

Siam Society in Bangkok, a nd the Alexander Library in Oxford.

SLATER, Peter 1970. A Field Guide to Australian Bir·ds : N on Passerines. Oliver

and Boyd, Edinburgh.

WHITE, Peter T. 1967. Hopes and fears in booming Thailand. N at. Geogr. 132 (I): 76-125 .